Technical Field
The present invention relates to semiconductor processing, and more particularly to fin field effect transistors and fabrication methods to improve carrier mobility.
Description of the Related Art
Many semiconductor devices employ fin structures for the formation of the field effect transistors (finFETs). High channel mobility and better/easier epitaxial growth processes are highly desired for very scaled complementary metal oxide semiconductor (CMOS) finFET integration. High Ge concentration SiGe is a promising channel material for performance improvements in p-type field effect transistors (PFETs) due to the expectation of high mobility. One problem in SiGe PFET fabrication is controlling n-type dopants (such as, As, P, etc.) since N-type dopants are known to have extremely high diffusivity in SiGe.